| 摘要: |
| 前黑素小体蛋白a (premelanosome protein, pmela)基因是黑色素合成通路中的关键基因之一，对动物的体色有着重要影响。为探讨pmela基因在虹鳟(Oncorhynchus mykiss)体色变异中的作用，本研究利用cDNA末端快速扩增(rapid amplification of cDNA ends, RACE)技术对pmela基因cDNA全长进行克隆并运用生物信息学方法分析该基因的序列特征，同时采用qRT-PCR比较pmela在野生型虹鳟(虹鳟)、黄色突变型虹鳟(金鳟)和杂交F1代受精期至孵化后3个月不同发育时期及成鱼不同组织中的相对表达量。研究获得pmela基因cDNA全长序列3 476 bp，包含2 532 bp开放阅读框，编码843个氨基酸。序列分析发现，Pmela为疏水性蛋白且存在PKD功能结构域。同源性比对发现，虹鳟Pemla氨基酸序列与红鲑(Oncorhynchus nerka)的同源性高达97.75%；进化分析结果显示，虹鳟与红鲑的亲缘关系最近，与人类(Homo sapiens)和小鼠(Mus musculus)的亲缘关系最远。qRT-PCR结果显示，pmela基因在虹鳟与金鳟胚胎及出膜后各时期均有表达，在受精期至16细胞期中的表达为虹鳟高于金鳟，出膜后该基因在金鳟背部皮肤中的表达均高于虹鳟，且在4细胞期、16细胞期、原肠期、神经期、体节期、心跳期、1 day post-hatching (1 dph)、3 dph、5 dph、7 dph、10 dph、1 month post-hatching (1 M)和2 M时期中，虹鳟与金鳟的表达存在显著差异。在各组织中，pmela基因在虹鳟与金鳟背部皮肤和眼睛中的表达显著高于其他组织。在杂交F1代中，pmela基因在不同发育时期和组织中的表达模式与双亲类似，且在大部分相同时期和组织中的表达与双亲存在显著差异。上述结果表明，pmela基因的表达量高低与虹鳟体色具有一定的相关性，且可能参与其体色的形成过程。本研究结果为进一步研究pmela基因在虹鳟体色变异中的作用提供基础资料。 |
| 关键词: 虹鳟 体色 前黑素小体蛋白a (pmela)基因 克隆 表达分析 |
| DOI：10.19663/j.issn2095-9869.20220601001 |
| 分类号: |
| 基金项目: |
|
| Cloning of the pmela gene in rainbow trout (Oncorhynchus mykiss) and its expression analysis in different developmental stages and tissues |
|
HUANG Jinqiang1, WANG Xiaolan2, LI Yongjuan3, WU Shenji4, ZHAO Lu5
|
|
1.College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China;2.College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730071, China;3.College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730072, China;4.College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730073, China;5.College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730074, China
|
| Abstract: |
| Premelanosome protein (pmela) is a key gene in the melanin synthesis pathway, which has an important impact on the skin color of animals. This study was conducted to explore the role of pmela in rainbow trout (Oncorhynchus mykiss) skin color variation. First, the full-length cDNA sequence of pmela was obtained using the rapid amplification of cDNA ends (RACE) technique, and bioinformatic analysis of the encoded protein was performed. Second, quantitative real-time PCR (qRT-PCR) was performed to detect the relative expression of pmela in different developmental stages [from the fertilized-stage to 3 months post-hatching (3 M)] and tissues of wild-type rainbow trout (WT), yellow mutant rainbow trout (YM), and their F1 generation. The results showed that the total length of pmela was 3 476 bp, including a 2 532 bp open reading frame encoding 843 amino acids. Bioinformatic analysis revealed that Pmela was a hydrophobic protein and had a PKD functional domain. Homology alignment showed that the similarity of the Pmela amino acid sequences of rainbow trout and sockeye salmon (Oncorhynchus nerka) was 97.75%. Phylogenetic analysis indicated that rainbow trout was most closely related to sockeye salmon and most distantly to humans (Homo sapiens) and mice (Mus musculus). qRT-PCR results showed that pmela was expressed in all developmental stages of WT and YM, and the expression level of the gene from the fertilized-stage to the 16-cell stage was higher in WT than in YM, whereas the opposite expression pattern was identified after hatching. Moreover, there were significant differences in the expression of pmela at the same stages between WT and YM, including at the fertilized-stage, 4-cell, 16-cell, gastrula, neurula, somites, heartbeating, 1 day post-hatching (dph), 3 dph, 5 dph, 7 dph, 10 dph, 1 M and 2 M. In various tissues, pmela expression was significantly higher in the dorsal skin and eyes of WT and YM than in other tissues. In the hybrid F1 generation, the expression pattern of pmela was similar to those of both parents, and there was a significant difference in expression at the same stages between the F1 generation and the parents in most of the same stages and tissues. The above results indicate that the expression level of pmela is correlated with the skin color of rainbow trout and may be involved in the formation of its skin color, which provides basic data for further studying the role of pmela in the variation of rainbow trout skin color. |
| Key words: Rainbow trout Skin color pmela gene Cloning Expression analysis |
